1. Field of Invention
The present invention relates in general to the field of flame retardancy. More particularly, the present invention relates to using flame retardant fillers prepared from bridged polysilsesquioxanes to impart flame retardancy to printed circuit boards (PCBs).
2. Background Art
In the manufacture of PCBs, connectors, and other articles of manufacture that employ thermosetting plastics (also known as “thermosets”) or thermoplastics, incorporation of a filler material as well as a flame retardant is required for rheology control (viscosity, flow, etc.) and ignition resistance, respectively. Typically, both attributes are not found in one material. That is, silica particles are generally the filler of choice for rheology control, whereas brominated organic compounds impart flame retardancy. Consequently, the base material (e.g., epoxy resin for PCBs, and liquid crystal polymer (LCP) for connectors) properties are compromised because a relatively large quantity of both a filler and a flame retardant is necessary to achieve the desired properties.
Therefore, a need exists for an improved mechanism for imparting flame retardancy to manufactured articles such as PCBs, connectors, and other articles of manufacture that employ thermoplastics or thermosets.